Morphogenetic processes in the development of the sexual reproductive apparatus of the fungus Neurospora will be studied by use of mutants that intervene in these processes. Electron microscopy is used to analyze instances of defective membrane assembly to effects of which are failure to delimit spores. Membrane from normal and defective material will be isolated and the membrane proteins will be compared by use of electrophoretic techniques. The same analytical tools will be applied to developmentally defective material obtained by phenocopying the mutant material by use of specific environmental treatments. In particular, the effects of biotin deficiency will be examined, earlier work having shown that biotin deficiency during the mating process results in defective membrane behavior as seen in the mutants that fail to delimit spores. Additional studies will be made of mutants characterized by altered cell shape associated with variant hexosamino glycan components of the cell wall.